Patent attributes
A dual-use air turbine system for a gas turbine engine of an aircraft is provided. The dual-use air turbine system includes a variable area air turbine mechanically linked to a spool of the gas turbine engine through a multi-speed gear set. The dual-use air turbine system also includes a plurality of valves in pneumatic ducting operable to direct an engine start air flow through an inlet of the variable area air turbine and drive rotation of the spool during an engine start mode of operation. The valves are further operable to direct an engine bleed air flow from a compressor section of the gas turbine engine through the inlet of the variable area air turbine and drive rotation of the spool during an environmental control system active mode of operation.
